511 research outputs found
Do peers see more in a paper than its authors?
Recent years have shown a gradual shift in the content of biomedical publications that is freely accessible, from titles and abstracts to full text. This has enabled new forms of automatic text analysis and has given rise to some interesting questions: How informative is the abstract compared to the full-text? What important information in the full-text is not present in the abstract? What should a good summary contain that is not already in the abstract? Do authors and peers see an article differently? We answer these questions by comparing the information content of the abstract to that in citances-sentences containing citations to that article. We contrast the important points of an article as judged by its authors versus as seen by peers. Focusing on the area of molecular interactions, we perform manual and automatic analysis, and we find that the set of all citances to a target article not only covers most information (entities, functions, experimental methods, and other biological concepts) found in its abstract, but also contains 20% more concepts. We further present a detailed summary of the differences across information types, and we examine the effects other citations and time have on the content of citances
On the Timing of Education
We propose a simple investment model which shows that, in the presence of fluctuations in and uncertainty about the opportunity cost of time, marginal individuals may choose to delay their education if the opportunity cost of time is temporarily high. Importantly, it is when the completion of the degree is uncertain, but likely enough that individuals will consider delaying their education. As a result, when returns to education are relatively low, education and timing of education will be sensitive to fluctuations in the opportunity cost of time. If return is high, delay is never optimal. These findings are supported by Swedish university enrolment patterns, and cross-country evidence on age of university freshmen.Timing of Education; Fluctuating Opportunity Costs
Between Facebook and Boas: Kichwa Indigenous Identity in Alto Napo and Challenges to Multiculturalism in Ecuador
This qualitative study examines contemporary Kichwa indigenous identity formation in the Alto Napo region of Ecuador through Bourdieu’s concept of symbolic capital. Following an extended-case method, I analyze the articulation of indigenousness (as an idealized expression of tradition) vis-à-vis the power relationships of the actors involved in such process. A combination between participant observation, daily field notes and twelve tape-recorded interviews during a two-month research allowed me to deconstruct essentialist portrayals and stereotypes of Kichwa indigenous peoples in Alto Napo, and confirm that their identity is hybrid, multiple and shifting. A comparative analysis between urban and rural social dynamics in the region further showed that the indigenous construction of the identity is influenced by power dynamics of recognition. Within Kichwa communities, the need to represent imagined traditional indigenous symbols does not surface on a daily basis in order to gain recognition; instead, other types of cultural capital are used to bind its members. These symbols, however, become dominant in contexts where the presence of nonindigenous peoples or State authorities marks the symbolic power they possess. The mechanisms and symbols used to construct the Kichwa identity thus shift according to the diverse power relationships that exist at the time of the representation. In order to gain value as an indigenous ethnicity and to show a symbolic reluctance to acculturation, the representation of an idealized traditional indigeneity becomes a strategy to authenticate their political, economic and cultural demands, which are identity based. This case study helps illustrate the connection between power structures, rights and identity through the analysis of indigenous symbolic capital in an Ecuadorian Amazon region
Deadlines and Distractions
We analyze the effect of deadlines on timing of effort when agents are occasionaly distracted. We show that agents precautiously work early when completion of the task is uncertain, but rather likely. Agents who are rarely distracted will always postpone effort since the risk of not completing is small. As a result, increasing the probability of being distracted may even increase the likelihood of meeting the deadline. We further show that introducing the possibility of having the deadline extended may improve the total probability of completing the task without reducing the probability of completing within the originally announced deadline.Deadlines; Timing of Effort; Optimal Incentives
Maximising the Degree of User Choice: a Simple Tool to Measure Current Levels of Quality of Life in Urban Environments
In this article, we present a simple methodology based on Max-Neef, Elizalde and Hopenhayn (1991) “human scale development” paradigm to measure current levels of Quality of Life (QoL) for urban environments. In this procedure, fundamental human needs form the study domains. We assess their fulfilment with a set of questions reflecting the subjective dimension of QoL. We sort questions into needs after two consecutive processes: a qualitative one involving local communities and/or expert groups, and a quantitative one involving the definition of weights for each question and per need. Complementarily, we add objective indicators to reflect the objective dimension of QoL. This way, we make possible a comparison between the two dimensions and a definition and computation of an integrative QoL. We argue that this method can be used to define more holistic urban quality indexes to improve decision making processes, policies and plans. It can also be seen as a tool to enhance bottom-up approaches and processes of urban analysis to create more liveable places for the dwellers
Living objects: towards flexible big data sharing
Data sharing and especially enabling third parties to build new services using large amounts of shared data is clearly a trend for the future and a main driver for innovation. However, sharing data is a challenging and involved process today: The owner of the data wants to maintain full and immediate control on what can be done with it, while users are interested in offering new services which may involve arbitrary and complex processing over large volumes of data. Currently, flexibility in building applications can only be achieved with public or non-sensitive data, which is released without restrictions. In contrast, if the data provider wants to impose conditions on how data is used, access to data is centralized and only predefined functions are provided to the users. We advocate for an alternative that takes the best of both worlds: distributing control on data among the data itself to provide flexibility to consumers. To this end, we exploit the well-known concept of object, an abstraction that couples data and code, and make it act and react according to the circumstances.Facultad de Informátic
Living objects: towards flexible big data sharing
Data sharing and especially enabling third parties to build new services using large amounts of shared data is clearly a trend for the future and a main driver for innovation. However, sharing data is a challenging and involved process today: The owner of the data wants to maintain full and immediate control on what can be done with it, while users are interested in offering new services which may involve arbitrary and complex processing over large volumes of data. Currently, flexibility in building applications can only be achieved with public or non-sensitive data, which is released without restrictions. In contrast, if the data provider wants to impose conditions on how data is used, access to data is centralized and only predefined functions are provided to the users. We advocate for an alternative that takes the best of both worlds: distributing control on data among the data itself to provide flexibility to consumers. To this end, we exploit the well-known concept of object, an abstraction that couples data and code, and make it act and react according to the circumstances.Facultad de Informátic
Intrauterine growth restriction and risk of diverse forms of kidney disease during the first 50 years of life
Background and objectives: Previous studies have shown that individuals with low birth weight (LBW) or small for gestational age (SGA) have higher risk of kidney failure. This study investigates birth-related exposures and risk of CKD and other kidney diagnoses.
Design, setting, participant, & measurements: The Medical Birth Registry of Norway has registered extensive medical data on all births in Norway since 1967. The Norwegian Patient Registry has registered diagnostic codes for all admissions and outpatient visits to Norwegian hospitals since 2008. Data from these registries were linked, and risk of CKD and other groups of kidney disease were analyzed using logistic regression statistics. LBW (below the tenth percentile), SGA (birth weight below the tenth percentile for gestational age), and preterm birth (<37 weeks) were analyzed as exposures.
Results: A total of 2,663,010 individuals were included. After a mean follow-up of 26 years (maximum 50 years), 4495 had been diagnosed with CKD and 12,818 had been diagnosed with other groups of kidney disease. LBW was associated with an odds ratio (OR) for CKD of 1.72 (95% confidence interval [95% CI], 1.60 to 1.90), SGA with an OR of 1.79 (95% CI, 1.65 to 1.94), and preterm birth with an OR of 1.48 (95% CI, 1.33 to 1.66). Analyses using diagnosis of CKD at stages 3–5 as end point showed similar results. Results were similar for men and women. We analyzed adjusted ORs for other groups of kidney disease and found that LBW was associated with an adjusted OR of 1.44 (95% CI, 1.33 to 1.56) for acute kidney disease, 1.24 (95% CI, 1.14 to 1.36) for GN, 1.35 (95% CI, 1.17 to 1.56) for cystic kidney disease, and 1.15 (95% CI, 1.06 to 1.25) for kidney disease resulting from kidney or urinary tract malformations.
Conclusions: LBW, SGA, and preterm birth are associated with higher risk of CKD in the first 50 years of life. Risk of other groups of kidney disease was less pronounced.acceptedVersio
Randomized heuristics for the Capacitated Clustering Problem
In this paper, we investigate the adaptation of the Greedy Randomized Adaptive Search Procedure (GRASP) and Iterated Greedy methodologies to the Capacitated Clustering Problem (CCP). In particular, we focus on the effect of the balance between randomization and greediness on the performance of these multi-start heuristic search methods when solving this NP-hard problem. The former is a memory-less approach that constructs independent solutions, while the latter is a memory-based method that constructs linked solutions, obtained by partially rebuilding previous ones. Both are based on the combination of greediness and randomization in the constructive process, and coupled with a subsequent local search phase. We propose these two multi-start methods and their hybridization and compare their performance on the CCP. Additionally, we propose a heuristic based on the mathematical programming formulation of this problem, which constitutes a so-called matheuristic. We also implement a classical randomized method based on simulated annealing to complete the picture of randomized heuristics. Our extensive experimentation reveals that Iterated Greedy performs better than GRASP in this problem, and improved outcomes are obtained when both methods are hybridized and coupled with the matheuristic. In fact, the hybridization is able to outperform the best approaches previously published for the CCP. This study shows that memory-based construction is an effective mechanism within multi-start heuristic search techniques
Multi-start methods for the capacitated clustering problem
In this work, we investigate the adaptation of the Greedy Randomized Adaptive Search Procedure (GRASP) and Iterated Greedy methodologies to the Capacitated Clustering Problem (CCP). In particular, we focus on the effect of the balance between randomization and greediness on the performance of these multi-start heuristic search methods when solving this NP-hard problem. The former is a memory-less approach that constructs independent solutions, while the latter is a memory-based method that constructs linked solutions, obtained by partially rebuilding previous ones. Both are based on the combination of greediness and randomization in the constructive process, and coupled with a subsequent local search phase
- …